With development of display technology and people's ever-increasing requirement for display image quality, the demand for a flat-panel display device with a high image quality and a high resolution has become increasingly common, and attracted more and more attention from manufacturer of display panels.
An array substrate is an important part of a display device, and the array substrate generally includes a thin film transistor, a pixel electrode, a common electrode and the like. Various elements on the array substrate are formed by adopting a patterning process during fabrication of the array substrate. The patterning process generally includes: exposing, developing, etching and stripping. The etching process includes wet etching and dry etching, which are used for patterning a metal film.
As shown in FIG. 1, in the prior art, a method of fabricating an array substrate is provided, and includes: sequentially forming a gate 1, a gate insulation layer, an active layer 2, a pixel electrode 3, a source 4-1 and a drain 4-2 on a substrate, a gate line 10 is generally formed while the gate electrode 1 is formed, and a data line 40 is formed while the source 4-1 and the drain 4-2 are formed.
The inventor has found that at least the following problems exist in the prior art: patterns of the gate 1, the active layer 2, the pixel electrode 3 and the like have already been formed on the substrate before the source 4-1, the drain 4-2 and the data line 40 are formed, such that the surface of the formed source-drain metal film is uneven and has height differences, and thus breakage is liable to occur when the patterns of the source 4-1, the drain 4-2, the data line 40 and the like are formed by wet etching, thereby resulting in failure of the array substrate.